Well pump crank



G. T. HUMPHREY WELL PUMP CRANK Jan. 17, 1939.

Filed Nov. 2, 1956 INVENTOR ATTORNEY.

Patented Jan. 17, 1939 WELL PUM'P CRANK Application November 2, 1936, Serial No. 108,748

5 Claims. (Cl. 74-591) PATENT OFFICE This invention relates to well pumping machinery and it has particular reference to a counterbalanced crank for well pumps.

The principal object of the invention is to provide a crank which is easily and inexpensively constructed, but one which has a high degree of efiiciency inasmuch as its design is such that a measure of flexibility or resiliency is obtained in operation and since provision is made for numerous adjustments of counterweights. The peculiar arrangement of ccunterweights enables the operator to impose the proper balance at precisely the right location on the crank relative to its pitman connection and this, in most cases, requiring only that the counterweights be pivotally displaced on their mounting.

Another object of the invention is to provide, as the body of the crank, a channel member which afiords retaining flanges for a pitman hearing block, the latter being capable of displacement longitudinally of the crank and relative to its pivotal point, to enable the operator to change the length of stroke without requiring that the pitman arm be disconnected from the crank pin.

With the foregoing objects as paramount, the invention has other and lesser objects as well as certain salient features of construction-to become manifest as the description proceeds, taken in connection with the accompanying drawing, wherein:-

Figure 1 is a side elevation showing a crank embodying the invention.

Figure 2 is an end view on lines Z2 on Figure 1.

Figure 3 is a detail section on lines 33 on Figure 1.

Figure 4 is a fragmentary perspective view of the split collar, receiving the shaft, and

Figure 5 is a perspective view of the crank, reduced in size.

Continuing with a more detailed description of the drawing, reference is primarily made to Figure 1 in which i designates a length of channel iron constituting the crank proper and to the flat side of the channel iron is welded a plate 2 of sheet metal. This plate is shaped preferably in the manner shown in Figure 1, that is, substantially fan shaped.

The extended edges of the plate 2 serve as mountings for the counterweights 3 which have the form of an equilateral triangle, for the purpose apparent in Figure 1. By forming these weights in this triangular shape, one point may be pivoted as at a to the plate 2 so that the counterweight so mounted may be swung to the right or to the left, as shown by the dotted lines in Figure 1, as best suits the requirement of balance. Particular notice will be taken that the opposing counterweights 3 may be pivoted on a line intersecting the wrist pin bearing block 4 and may be moved to a position on either side of this line, either with one plane parallel to the major axis of the crank I as shown in dotted lines, or at an angle of approximately 45?. This feature is important since it has been found in operation that normally, the best results are obtained when the load is carried at a point on the arm close to the wrist pin bearing 4. However, conditions requiring a variation from this setting are met by pivotally mounting the weights 3 so that they may be readily swung to a more desirable or effective position without requiring the removal of but a single bolt b. i

To accommodate the weights 3, the plate 2 is provided with horizontally and vertically alined apertures c so that the weights 3 may be moved to several positions along the length of the plate as well as being capable of pivotal displacement as described for minute adjustments. If required, the counterweights 3 may be removed entirely leaving only the weight 5, slidingly interposed between the flanges of the channel iron crank arm I. Bolts 6 serve to hold this weight securely in adjusted position and when found to be necessary or desirable, the weight 5 may be so moved in the channel that a portion protrudes therefrom, as shown by the dotted lines in Figure 1. Should the crank be required to counterbalance an extremely heavy load, it is an easy matter to dispose the sliding weight 5 in the dotted position, mount the counterweights 3 on the pivot second from the left in Figure l and dispose them so that they will lie in the position shown in dotted lines. As a means to insure rigidity of the counterweights 3, an iron strap l extends from one pivotal point a to the other, as shown.

It has been stated that the crank is constructed so that a change in stroke may be made Without removing the wrist pin of the pitman (not shown). This is accomplished through the medium of the slot 8 made longitudinally in both the channel iron web and the plate 2 so that the integral pin 9 of the bearing block 4 may slide therein. This pin is shown in Figure 2. When adjustment is required in the stroke, bolts m are removed, the block 4 replaced in the desired position and the bolts l0 reinserted. This adjustment obviously requires only a short period of time and requires little labor.

The split collar H shown in detail in Figures 3 and 4 is provided with reinforcing webs l2, which are preferably cast integrally with the collar and the block l3, lying between the flanges of the channel member I. By thus making the bearing assembly in a single piece, it is more readily applied to the channel member, since it is only necessary to weld along the contiguous faces d of the webs, block and plate 2 to securely hold the parts together.

The collar I l is split as shown, and is provided ,with parallel flanges l4 and a keyway I5. When mounted on the shaft, the bolts l6 are tightened to bind the collar on the shaft for operation.

Manifestly, the construction as shown and described is capable of some modification and such modification as may be construed within the scope and meaning of the appended claims is also considered to be within the spirit and intent of the invention.

What is claimed is:-

1. A crank for well pumps including a channel member having a longitudinal slot therein midway between its flanges, a plate aiflxed to and parallel with the flat side of said member whose edges extend beyond the flanges of said channel member, a wrist pin block slidably disposed between the flanges of said channel member whereby the wrist pin will extend through said slot, means to secure said block in a plurality of adjusted positions, a mounting collar afixed in one end of said channel member, a pair of counterweights having pivotal points along the extended edges of said plate and capable of being tilted to adjusted positions and at extended points on said plate relative to said wrist pin block, and means to secure said counterweights to said plate at said pivotal points and at points spaced from the pivots of said counterweights.

2. A crank for well pumps including a channel member having a fixed bearing in one end and a slidable wrist pin block intermediate its ends, means to secure said block in a plurality of adjusted positions, a plate affixed to said channel member whose edges extend at right angles to the flanges of said channel member and which are provided with spaced perforations, counterweights capable of being pivoted at a series of selected points on either side of said channel member whereby to be tiltable to vary the balance of said crank relative to the fixed posititon of said wrist pin block, means to secure said counterweights inadjusted positions relative to their pivotal points; and a slidable counterweight in the end of said channel member opposite said fixed bearing, and means to secure said slidable counterweight in said channel member.

3. A crank for well pumps including a member of greater length than width and having relatively parallel flanges extending through its major axis and at right angles to the plane of said member, a fixed bearing block disposed between said flanges at one end, a slidable counterweight disposed also between said flanges, means to secure said counterweight to said member in adjusted positions, a bearing block between said flanges intermediate their ends, means to secure said bearing block in adjusted positions, a pin extending through a slot in said member and bearing block, a pair of oppositely disposed counterweights pivotally mounted on said member whereby their bulk may be fixedly disposed in spaced relation to said flanges, and means to secure said counterweight in adjusted positions relative to their pivotal points.

4. A crank for Well pumps including a member having spaced and relatively parallel flanges with flanges extending at right angles to the exterior surfaces of said first flanges and throughout the length of the latter, a fixed bearing block intermediate and at the end of said first flanges, a slidable bearing block intermediate the ends of the latter having a protruding pin, means to secure said pin in a series of adjusted positions, a pair of oppositely disposed and pivoted counterweights, means to secure said counterweights in adjusted displacement relative to their pivotal points and on said second flanges exteriorly of said first flanges, a slidable counterweight disposed between said latter flanges at the end thereof opposite said fixed bearing block, and means to secure said slidable counterweight to said member in adjusted positions.

5. A counterbalanced crank for well pumps incluidng a plate of greater length than width having flanges extending in relatively parallel relationship through its major axis, a fixed bearing between and at one end of said flanges, a slidable counterweight at the opposite end thereof, means to'secure said counterweight in adjusted positions, a wrist pin block intermediate said flanges and said bearing and counterweight, means to secure said block at adjusted positions, counterweights arranged for pivotal connection and securement at a number of spaced positions and tiltably disposed at angles on said plate on either side of said flanges relative to the secured position of said wrist pin block, and means to secure said counterweights is adjusted positions.

GEORGE T. HUMPHREY. 

